Bead for pneumatic tires



Aug. 21, 19,28. l

R. c. PIERCE BEAD FOR PNEUMATIC TIRES Filed June 18, 1927 Patented Aug. 2l, 1928.

UNITED STATES" PATENTf-FPICE- nonnnr c. PIERCE, 4or Nuns, MIcnIeAN, assrerqon To NATIONAL-STANDARD coni PANY, or NILEs, MICHIGAN, aconrona'rron or -inrcrnauim4 Baan ron INEUMATIo Trans.

i Appnafnn mea :une 1e, 1m' man 110,199,808.

. A'This invention relates to improvements in beads for'pneumatic tires. Y

Among the features of my invention is the provision of a tire bead provided with are-V inforcement which may be easily and chea ly manufactured and which is substantially non-stretchable.

Other features and advantages of my invention .will appear more fully as I proceedv with ymy s ecifieation.

In that orm of device embodying the feaconventional tire casing provided with the usual bead 42,'which is formed of a suitablerubber composition, the vbead being of a cross-section correspz'inding to the tire in which it is desiredto use the same.

I shall now describe .the reinforcement forminga part of the bead. In order to.

Imakethe remforcementfor the bead I take any". suitable reinforcing element. or tape, having sufficient tensile. strength, For example, 'the reinforcini 1 element used may consist of' three lpara lelwires or tenslon.

members 1'Ohel d inparallel relation by the thinner strand 11 woven'diagonally back and forthl as shown. f Such an element, consisting of the three wires 10 bonded or 'held together by the wire" 11, or any other suit able element may be used. In the use of such an element, the same is convolutely disposed in the tire bead as many. turns as desired'being formed. for example, there may Abethree wraps o r convolutionsl of the element as shown in" the drawings. If desired, these wraps ma be madeion the mandrel or form as the bea is being made up, or the element may be so disposed apart from the bead and formed *into'a' completed annuluswhich is inserted in the bead as the same i's formed. In either case, however, as the convolutions'of the element are formed, a strip or strips of im-4 pregnated fabric or fibrous ribbon as indicated by 12 are placed between adjacent Sur-Y lar strip 12 is place tures of my invention shown 'in the accomn making my heath faces of the reinforcin element and a simiinside of the Inner wrap andfanother 12h outside of the outer -wra such fibrous strips being also convolute y disposed in the tire bead, and this ribbon or stri .12 and-the element 10 beingsubstantia y parallel throughout their l lengths. This fabric or'fibrcus ribbon, tape, or other material, is preferably impregnated fwith rubber compound similar to the rubber compound used inthe manufacture of the completed bead,4 so that as the bead is formed, in. the curingprocess, the reinforcing element,- and the various convolutions thereof, become firmly united together, and embedded inthe tire bead. The annulus thus formed of the turns of the reinforcing element with the strips 12, 12 and 12b is preferably incasedin a strip of material 13, commonly known asa Hipper strip, which becomes a part of the bead in the final forming process.`

The formvshown in Fig. 3 is substantially the same as that shown in'Fi 2 except that the impregnated fabric or brons ribbons or strips 12, 12a and 12b. are made somewhat wider than the.ele ment 10 so that they have overlapping edges as indicated by 12 which curve around the ed es of the outer wires 10 lof the reinforcing e ement, thus more completely` enclosing the convolutions of the element in the impregnated fabric or fibrous ribbon.

In the form shown in Fig. 4,1 have used a reinforcing element consisting of the wires 10, which are not'v -held together by a bonding wire 11 but which are held together by being embedded in a rubber compound 14.

That is,in the form shown in Fig. 4, the reinforcing element is a sort of tape or band consisting ofthe three wires 10 embedded in a rubber 'compound 14. This reinforcing element is convolutely disposed to `form an annulus (three wraps being shown) in the same manner as the element shown in Figs.`

2 'and 3, and there is laid between the turns of this element a similar rubber impregnated fabric or fibrous ribbon 12. A similar ribbon 12* is laid under the bottom layer and another 12b on the top layer of the element.

While I have shown and described cer- I tain embodiments of m invention, it is to be understood'that it 1s capable of many modifications.- Changes, therefore, 1n the construction and arrangement may be made v without departing from the spirit and scope of the invention disclosed in the appended claims, in which it is my intention toclaim all novelty-in my inventionl as broadly as possible in view of the prior art.

What I claim is new, anddesire tosecure by Letters Patent, is:

1. A tire bead having ernbeddedjthereina convolutely disposed reinforcing element, the wraps of said element being separated by a convolutely disposed fibrous ribbon impregnated with rubber, the ribbon and the.

out their lengths, and the whole being-1m cased in a ilipper strip.

3. A tire bead having embedded therein a convolutely disposed reinforcing element the wraps of said element being separated by a convolutely dis osed fibrous ribbon impregnated with rub er, the ribbon and the element being parallel substantially. throughout their lengths, andaI similar rubber. im pregnate'd librous ribbon lying inside the inner wrap and outside lthe outer-wrap.

4. A tire bead having embedded therein a convolutely disposed, reinforcing element, the wraps of said'element being sepa` rated by a convolutely disposed fibrous rib-- bon impregnated with'l rubber, the Iribbon and the element bein' parallel substantially throughout their lengt s and a similar rubber impregnated fibrous ribbon lying inside the inner Wrap and o'utsidetheouter wrap, the whole being incased in a flipper ystri 5. A tire bead having embedded t erein a convolutel disposedl reinforcin element, a iibrousrib on impregnated with rubber lying between thev wraps of said element, and a .similar fibrous ribbon impregnated with rubber lying inside the inner wrap and outside the outer wrap, said ribbons being wider than said element whereby the edges thereof are bent around the edges of the element when the same is incased in a flipper strip.

In witness whereof, I have hereunto set my hand this 15th day of June, 1927.

ROBERT o. PIERCE. 

